Electrical measuring-instrument



(No Model.) '2 Sheets-Sheet 1.

I E. WESTON. ELEGTRIGAL MEASURING INSTRUMENT.

No. 444,804. Patented Jan. 13, 1891.

IIIIHIIIIIIIHE $140M 4mm MANOR/V57.

(No Model.) I 2 SheetsSheet 2. E. WESTON.

ELECTRICAL MEASURING INSTRUMENT. No. 444,804. Patented Jan. 13, 18 91.

IIIIIIIIIIIIA 'II'IIIIIIII I A I 7 5 WITNESSES: INVENTOI? a Mam ATTORNEY.

maintained in a circuit or for indicating the UNTTE STATES PATENT Urrrcn.

EIMVARD IVESTON,OF NEIVARK, NEIV JERSEY.

ELECTRICAL MEASURING-INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 444,804, dated January 13, 1891,

Application filed June 11, 1890.

To all whom it may concern:

Be it known that I, EDWARD Wnsrox, of Newark, Essex county, New Jersey, have invented a new and useful Improvement in P0- tential-Indicators or Voltmeters, of which the following is a specification.

My invention relates to an instrument for showing variations in potential of the current electrical pressure of a current in volts.

My invention consists, broadly, in an elec trical measuringinstrulnent embodying two fixed coils and a movable coil having their longitudinal axes in prolongation, the said movable coil being supported between said fixed coils in inductive proximity thereto and connected in circuit therewith, in combination with means for showing the extent of movement of the movable coil, which extent of movement will bear a relation to the magnitude of pressure of current in the circuit.

My invention further consists in the various instrumentalities and combinations, as hereinafter described, and more particularly set forth in the claims.

In the accompanying drawings, Figure 1 is a front elevation of my potential-indicator. Fig. 2 is a skeleton diagram showing the connections in the instrument. Fig. 3 is a vertical section on the line X X of Fig. 1. Fig. 4 is an enlarged detail view showing the mode of connection of the springs with the ring or coil which they support.

Similar numbers of reference indicate like parts.

38 is the case of the instrument, provided with the heads 39 and 40, and made of mag netic material. Centrally supported on the heads and extending into the said case are the cores or pole-pieces 41 and 42. Within the case and surrounding said pole-pieces is a ring 43. The pole-pieces or cores 41 and 42 are therefore of like magnetism, and the ring 43 is of opposite magnetism, so that an intense magnetic field of force is produced in the annular space between said ring 43 and the said pole-pieces 41 and 42.

Upon the pole-pieces 41 and 42 and supported on two spools 0r bobbins of non-magnetic material are coils 44 and 45 of insulated wire, as shown. Surrounding the extremities Serial No, 355,095. (No model.)

of both pole-pieces 41 and 42 and disposed in the annular space between said pole-pieces and the ring 43 is a ring 46, of brass or other non -inductive material, around which is wound a coil of line wire 47. This ring is supported in place by the spiral springs 48 and 49.

across the ring 46 is a diaphragm 52, having a central aperture which receives a projection on the flanged boss 54. The threaded extremity 50 of the spring 48 enters said boss on one side of the diaphragm. The boss 54 is secured in place by the collar 55 and nut 56, which is received on the threaded end 51 of spring 49.

Passing through the heads 39 and 40 are hollow screw-bolts 57 and 58. In each bolt is a bushing 59 ()0. The threaded rods (31 and 62 at the ends of springs 48 and 49 pass through said bushings 59 and and are secured by nuts 63. By setting up the nuts more or less the springs 48 and 49 can be regulated and the diaphragm 52 adjusted midway between the ends of the cores or polepieces 41 and 42. On the exterior of the heads 39 and 40 are provided caps 64, which cover the devices which secure the ends of the springs. Secured above the case 38 is a frame 65, in which are set two plates 06 and 67, of glass or other translucent or semi-translucent material. On one of said plates is inscribed a scale-marking, which may be in volts, substantially as shown in. Fig. 1. Extending up between the plates 66 and G7 is an index-needle 68, which is fastened to the ring 4-6. The case is supported on a suitable standard, such shown at 69.

The circuit-connections in the instrument will be readily understood from the diagram, Fig. 2, the circuit proceeding by wire afrom one terminal through the coil 45, and thence by wire I) to one spiral spring 49, thence to the suspended coil 47, opposite spring 48, by wire 0 to opposite fixed coil 44, and finally by wire (I to the other terminal of the instrument. As the extremities of the cores 41 and 42, which enter the suspended coil 47, are of like name, it follows that the coil when the current passes will tend to move bodily in the direction of the longitudinal axes of the Said springs have at each extremity. threaded rods, as 50 51. Fig. 4. Extending between the terminals of the instrument. As

the coil is thus moved it is given a rotary motion by the action of the springs 48 and 49,

and in this way the coil causes the vibration of the needle (38, which is attached to it over the scale-plate, so that the extent of rotation of the coil, and hence the difference of potential between the terminals of the instrument, is thus visually indicated.

I claim 1. In an electrical measuring-instrument, two fixed coils and a movable coil having their longitudinal axes in prolongation, the said movable coil being supported between said fixed coils and in inductive proximity thereto, and means for indicating the extent of movement of said movable coil, the said coils being connected in circuit.

2. In an electrical measuring-instrument, two fixed coils'and a movable coil having their longitudinal axes in prolongation, the said movable coil being supported between said fixed coils in inductive proximity and movable With reference thereto and rotary on its axis, and means for indicating the extent of rotation of said movable coil, the said coils being connected in circuit.

3. In an electrical measuring-instrument, twoelectro-magnetshavinglikepolesopposed, a coil surrounding said poles and free to move in the direction of the axial line of said n1agnets, and means for indicating the extent of motion of said coil, the said magnets and coil being in circuit.

4. In an electrical measuring-instrument, two electro-inagnets, each having one pole surrounding the other and having like poles facing, a coil supported and free to move in an axial direction in the annular space between the poles of said magnets, a vibrating index-needle, and mechanism transmitting motion from said coil to said needle, the said magnets andcoil being connected in circuit.

5. In an electrical measuring-instrument, two electro-magnets having like polarextremities of their cores facing and ring pole-pieces surrounding said extremities,- in combination with a coil supported and free to move in the annular space between said ring pole-pieces and cores, and means for indicating the extent of movement of said coil, said movable coil and magnet-coils being in circuit.

6. In an electrical measuring-instrument, two electro-magnets havinglike polar-extremities of their cores facing and a ring pole-piece common to both surrounding said extremities, in combination with a coil supported and free to move in the annular space between said ring pole-piece and cores, and means for indicating the extent of movement of said coil, said movable coil and magnet-coils being in circuit.

7. In an electrical measuring-instrument, two electro-magnets havingtheir longitudinal axes in prolongation and piovidedwith hollow cores with like polar extremities facing, a coil surrounding said polar extremities, and a suspension device for said coil extending through said cores, the said magnets and coil being connected in circuit.

8. In an electrical measuring-instrument, two electro-magnets having their longitudinal axes in prolongation and provided with hollow cores with like polar extremities facing, a coil surrounding said polar extremities, and two opposed springs secured to saidcoil and extending, respectively, through said cores, the said magnets and coil being connected in circuit.

9. In an electrical measuring-instrument, two electro-magnets having their longitudinal axes in prolongation and provided with hollow cores with like polar extremities facing, a coil surrounding said polar extremities, two opposed springs secured to said coil and extending, respectively, through said cores, and means for adjusting the tension of each of said springs, the said magnets and coil being in circuit.

10. In an electrical measuring-instrument, the combination of the coils 44 and 45, having pole-pieces 41 and 42 of like na|ne, with the suspended ring 46, carrying the coil 47 and surrounding said pole-pieces, and means for indicating the extent of movement of sa d ring, said coils 44, 45, and 47 being in circuit.

11. In an electrical measuring instrument, the combination of the coils 44 and 45, having the hollow cores 41 and 42, with polar extremities of like name facing, the ring 46, carrying the coil 47 and surrounding said polar extremities, the opposed springs 48 and 49, secured to said ring and extending, respectively, through said hollow cores, and an indexneedle and scale for showing the rotary mo vement of said ring, said coils 44, 45, and 47 being connected in circuit.

12. In an electrical measuring-instrument, the combination of the coils 44 and 45, having the hollow cores 41 and 42, with polar extremities of like name facing, the ring polepieces 43, surrounding said polar extremities, the ring 46, carrying the coil 47 and disposed in the annular space between said ring polepiece 43 and the polar extremities of said core, the opposed springs 48 and 49, secured to said ring and extending, respectively, through said hollow cores, and an indexneedle and scale for showing the rotary movement of said ring, said coils 44, 45, and 47 being connected in circuit.

M. Boson, FRED KEMPER. 

